Laminar Burning Velocity Measurement of CH4/NH3/H-2-Air Premixed Flames under Engine Relevant Conditions

Accessibility of affordable clean energy is importantfor accomplishingeconomic development and advancement alongside progress in environmentalchange. In this pursuit, the present study proposes an alternate ternaryfuel blend with better fundamental combustion characteristics thannatural gas/methane. This work focuses on the laminar burning velocitymeasurement of a CH4/10% NH3/H-2 ternaryblend under elevated pressure and temperature conditions using theexternally heated diverging channel technique. The NH3 volumefraction is maintained at 10% by volume in a H-2:CH4 (1:4) fuel blend and is comparable to a CH4 +air mixture in terms of mixture burning velocity and flame temperaturewith & SIM;25% lower carbon emissions. The experimental measurementsare obtained for elevated temperatures (300-750 K), pressures(0.1-0.5 MPa), and & phi; = 0.7-1.4 equivalence ratiorange. The measured mixture burning velocities of CH4/NH3/H-2 mixtures are nearly similar to CH4 + air mixtures at elevated pressures. The pressure and temperatureexponents are derived to establish their codependency. Therefore,a revised power-law correlation is proposed for burning velocity variationat high pressures and temperatures. Predictions of Li and Okafor kineticmodels coincide well with the present experimental measurements upto 0.5 MPa, whereas Shrestha and improved GRI 3.0 mechanisms overpredictthe velocity values. The reduction in HCO to H conversion reducesthe burning velocity with pressure increment. The present work competentlycompares the combustion characteristics of CH4/NH3/H-2-air mixtures with CH4 fuel and establishesthe proposed ternary blend as a viable solution to attain sustainabilitygoals with reduced carbon emissions.

Automated summary

The present study proposes an alternate ternary fuel blend with better combustion characteristics than natural gas/methane. Experimental measurements show that the CH4/10% NH3/H-2 ternary blend has comparable burning velocity and flame temperature with lower carbon emissions compared to a CH4 + air mixture. This proposed blend is considered a viable solution for achieving economic development, environmental improvement, and sustainable development goals.